Red light exposure could help reduce your blood sugar levels after eating, new research suggests.
The study, published in the Journal of Biophotonics, found that shining a red light on a person’s back could help benefit blood glucose.
The findings revealed that a specific frequency of the light used for 15 minutes led to a 27.7 percent reduction in blood sugar levels after eating.
Red light exposure also reduced maximum glucose spiking by 7.5 percent. Spikes refer to a rapid increase in the amount of sugar in your blood after you have a meal.
The research team also suggested that lengthy exposure to blue light, which is emitted from devices like phones, laptops, and TVs, could have significant long-term consequences for human health.
Given the prominence of LED lighting in modern life, the authors warned that this may be a potential “health span time bomb”.
They explained that blue light on its own can drive disrupted blood sugars that may lay the dangerous groundwork for diabetes.
The good news is that this can be partly addressed by spending more time in sunlight, which has a balance of red and blue light.
Professor Glen Jeffery, Professor of Neuroscience at the UCL Institute of Ophthalmology, said: “We now live in a world where blue light is dominant because although we do not see it, LED lights are dominant in blue and have almost no red in them.
“This reduces mitochondrial function and ATP production. Hence our internal environments are red-starved.
“Long-term exposure to blue light is potentially toxic without red. Blue light on its own impacts badly on physiology and can drive disrupted blood sugars that may in the long run contribute to diabetes and undermine health spans.”
The researchers recruited 30 healthy people, who were put into two groups – 15 in the 670 nm red light group, and 15 in the no light group.
They were then asked to drink glucose dissolved in water and have their blood glucose levels recorded every 15 minutes over the next two hours.
The study found that red light at a frequency of 670 nanometres (nm) stimulated energy production within mitochondria, the tiny powerhouses within cells, leading to increased consumption of glucose.
People who received red light exposure exhibited a reduced peak in their blood glucose level and reduced total blood glucose.
Dr Michael Powner, lead author of the study and senior lecturer in neurobiology at City, University of London, said: “It is clear that light affects the way mitochondria function and this impacts our bodies at a cellular and physiological level.
“Our study has shown that we can use a single, 15-minute exposure to red light to reduce blood sugar levels after eating.
“While this has only been done in healthy individuals in this paper, it has the potential to impact diabetes control going forward, as it could help to reduce potentially damaging glucose spikes in the body after meals.”
Keith Frayn, emeritus professor of human metabolism and emeritus fellow at Green Templeton College, University of Oxford, explained that if these findings are confirmed later in people with diabetes, this could be the foundation of a “useful intervention”. However, he warned they should be regarded as “quite preliminary”.
Frayn added: “More investigations would be needed before we can fully assess this effect. Importantly, we need to know whether this is a true metabolic effect, or whether, for instance, the warming effect of the red light exposure alters patterns of blood flow, potentially altering the nature of the blood sampled by pricking a finger. We also need more information on what happens to the glucose that doesn’t appear in the blood.”
